Spiral sewing machine



Sept. 6, 1955 v. PASQUINI ET AL SPIRAL SEWING MACHINE Filed June 16,

INVENTORS V. Pasgu/m' BY V. Gaerrini W,544+M li'fforne s United States Patent SPIRAL SEWING MACHINE Vittorio Pasquini and Vincenzo Guerrini, Pavia, Italy, assignors to Vittorio Necchi S. p. A., Pavia, Italy Application June 16, 1953, Serial No. 362,098

Claims priority, application Italy June 16, 1952 8 Claims. (Cl. 112-2) The present invention relates to an apparatus adapted to permit the semi-automatical or automatical sewing of seams having spiraloid shape and in particular archirnedean spiral shape, utilizing sewing machines having ordinary features, with which the instant apparatus is combined without any modification or working of the members of the machine.

In particular the present invention concerns an apparatus of the type and for the uses indicated, of industrial production, the application and use of which is comparatively simple, and which is adapted to permit the sewing of seams of the type indicated with different pitches or inclinations of the helix, and on products of different thickness, diameter and consistency.

It is known that in the production of many industrial articles and items composed of a number of superimposed layers of fabric, felt or other material, for example in the production of buffs or wheels for rotary polishing machines, for buffing machines, filtering disks for oil-mills (disk filters, percolators), or other applications, it is necessary to sew numerous seams to unite the said disks. In general, such seams are in the form of concentric circles, which is the cause of some inconveniences, and in particular of an interruption in the sewing operation, to pass from one circle to the other, as well as in the use of the product as a boiling wheel, because the progressive wearing at the periphery of the wheel or disk reaches simultaneously the whole of a circular seam causing its instantaneous spoiling and consequent projecting of fragments.

It is also known that spiral seamswhich from the point of view of the mutual bond between the various layers composing the discoidal product are not inferior to seams in concentric circlesdo not oifer the inconveniences indicated above, because they are sewn along a line extending from the periphery to the proximity of the centre of the disk, and also because the spoiling of the seam due to the progressive Wear of the disk takes place point by point, without causing any inconveniences.

For the sewing of such spiral seams however it is indispensable that the discoidal material to be sewn, besides rotating about its own centre during the sewing operation, should be progressively drawn nearer to the sewing mechanism of the machine with uniform or at any rate predetermined motion and with translatory movement along a line passing through the point in which the stitches are applied.

Also, it is known that there have been carried out numerous experiments and there have been produced some apparatuses which deriving their movement from the sewing machine subject the said discoidal material to such movements. Those apparatuses however require the use of sewing machines built especially for that purpose or at least substantially modified in some of their parts.

It is a specific object of the present invention to provide an apparatus, which does not offer the inconven- 2,716,952 Patented Sept. 6, 1955 iences mentioned above, which can be used with any ordinary sewing machine, and in which there are provided supporting means for the discoidal material to be sewn, means for tying its centre to a freely rotating body in such a manner as to enable said discoidal material to rotate under the action of the tangential thrust imparted thereto by the ordinary normal feed mechanism of the sewing machine, and a mechanism connected to said rotating body and made in such a manner that it causes the progressive approaching of the latterto the sewing mechanism of the machine, due to the rotation of such body.

A practical embodiment of an apparatus according to the novel principles set forth hereinbefore, in one of its possible forms of embodiment, together with its generic and specific characteristics and with the advantages deriving therefrom, will be well understood from the detailed description that follows. and with the aid of the accompanying drawings, wherein:

Fig. 1 represents in perspective view and in diagrammatical form the assembly of the operative parts comprised in one example of embodiment of the apparatus in question;

Fig. 2 represents said apparatus, in top view, limited to its functional parts; I

Fig. 3 represents 'upon a larger scale, a lateral view partly in section, showing a detail of the combination of parts for holdingthe discoidal material to be worked in the apparatus.

Fig. 4 represents similarly a detail of the mechanism causing the translatory movement of said material by its rotation.

Fig. 5 represents the gripping feeder for the discoidal material to be sewn.

With particular reference to the drawings: the apparatus in question, as diagrammatically represented in Fig. 1, comprises a means 1 adapted to fix the centre of I the discoidal material 2 on which the steam has to be I corresponding to the specific production, effects sewing.

Movement is imparted to the discoidal material 2 by the conventional gripping feeder of ordinary sewing machines (see Fig. 5). The grip 28 moving along a rectangular path, feeds the material interposed between said grip and the cloth-pressing member 29. The movement in rectangular path is obtained by the composition of the movements of the two levers 30 and 31 which oscillate about the shafts 32 and 33 and derive their own motion in a known manner from the upper shaft. The support 34 connected to the two said levers is rigid with the grip 28, in such a manner that during its movement the material is dragged only when the needle 35 does not penetrate into it.

Owing to the movement of rotation which is imposed by the operation of the sewing machine to the discoidal material 2, the latter drags along with it in rotation the said rotating body 3, which by means of a mechanism of any type compels the carriage 4 to displace itself, as a function of said rotation, along the respective guides 5, 5 or along the predetermined trajectory. Generally, any mechanism adapted to transform a rotary movement of a material into a translatory movement, for example a system of racks, of helical bars, or other, may be employed for the purpose.

In particular, as visible in Figures 1 and 2, the appatus in question comprises moreover a second carriage 8,

placed below the plane Q of th sewing machine, and in turn slidable along guides 10, 10 in a direction orthogonal to the direction of movement of the first carriage 4. on said second carriage 8 there is placed diagonally a bar 11 having a guidegroove 12 ..whereinthere. slides the lower: endofithe rotating body.- 3,. andua rack .13 with...

which engages a pinion- 14 rigidwvith'saidrotatingbody.-

In this way, by effectefinerotationof thevlatter th pinion 14 is-compelled to roll without gliding alongithebar.11, which is displacedfreely; with thecarriagefl, in

a vtranversal sense, but,. owing ,to its diagonal arrange-.

ment, it obliges the. rotatingbody. 3, togetlger with the carriage, 4 and thediscoidalamaterial 2,. to displaceitself I alonglthe guides S, .totgo towardsqorawayfrom the sew-r ingot stitching point 6. The translatony 'movement of said carriage 4 is a function of the component of the inclination ofathe bar 11 in the direotionofihe guides 5,-and consequently inan apparatus according tothe: invention the ratio between the translatory travel of the moreover, according to the longitudinal development of the pitch circle of engagement of the'pinion 14.

In case discoidal materials 2 of limited consistency have :to be sewn, that is -to-say,.-materials which might suffer damage in transmitting the rotary movement re-.-

ceived from thetangentialthrusts-of the feed mechanism of the sewing machine, to the rotating body 3, the rotation of'which is opposed by the resistances of the mechanisms pulley 17 (Fig. 1); said weight may ;be =varied-at will according to the kind of work to be doneand'to thekind of material to be worked.

In order to make the discoidal material12 rigid with the rotatingbody 3 (which; in practice, maybe embodied in the shape of a simple vertical shaft, supported and rotating within. convenient supportingmeanslS, as visible in Figures 3 and 4), the means 1 for fixing said materialmay constituted by a cap 19 (Fig. 3) that can be connected e. g. by means of a bayonet joint20 to the top: end

210i said shaft 3, said cap'19 beingprovided with a supporting flange 22 which is elastically pushed e. g. by a spring 23, over said material 2, against a lower supporting flange 24, rigid with said'shaft 3, and preferably provided with sharppoints 25 so as to ensure the angular constraint between the material and shaft 3.

In particular, the lower end of said shaft 3 is provided with a small roll 26' (Fig.;4) for sliding in theguide -12,

constituted by a groove obtained in the bar 11. The

rack 13 is provided on the flank of a builtup bar 27, whichis preferably removably fixed to said bar 11 in such a way that, if so desired, it can be mounted in the oppositeposition 27a. Said reversalof position permits obtaining a reversal in the sense of translatory movement of the materialysubjected to rotation in the same sense;-

this is advantageous for the purpose of pre-arranging the apparatus-for the sewingof' a spiral seam from the centre towards .the periphery of the material, or vice versa.

However, since the apparatus in question has been de-- 4 v, scribed and represented only by way of indicative example without limitation, it is understood that it may comprise mechanisms of different type and construction, provided there be equivalence of operation, for the purpose indicated, and at any rate it admits variants and modifications and even numerous improvements without departing from the scope .of'the present invention, it being understood that any apparatus embodied on the basis of the novel principles set forth hereinbefore and having any one or more of the characteristics indicated in the following claims falls within the .scopeof. the invention.

What we claim is:

1. Spiral sewing means for a sewing machine-having work feeding means comprising a body rotated by said work feeding meanscarryin'g :the material to be sewn, a first carriage movably mounted with translatory motion towards or away from the sewing point supporting said body, a pinion mounted on said body, a second carriage movable angularly with respect to the movement of-said.-. first carriage and a rack meshing with said pinionmount-t ed on saidsecond carriage. diagonally withLrespectto-thew movement of said second carriage,-

2. Means as claimed in claim 1 wherein said rack is" mounted on said second carriage to permit variations of. inclination with respectto the. movement-of said second carriage,

3. Means as, claimed in claim 1, wherein said second-.- carriage is provided with. a groove paralleltosaid rack: and a roller is mounted on said body. to run insaid' grooves 4. Means asclaimed in claim 1, wherein said rack is mounted on said second carriagetopermit variations of inclination with respect to the movement of said second carriage, and said second carriage is. provided with agroove parallel to said. rack anda roller. is 'mountedon said body to run in said groove.

5. Spiral sewing means for a sewing machine havingsi work feeding means comprising .a body. rotated by saidm work feeding means carrying the material to be sewn, means on said body for maintaining the material to be: sewn both axially and in rotation a first-carriage mov ably mounted with translatory motion towardsor-away from the sewing point su porting .said body, a pinion. mounted on said body, a second. carriage movable angu-v larly'with respectto the movement of said first. carriage and 'a rack meshing with saidwpinion mounted on said second carriage diagonally with respect-to the'movementof "said second carriage.

6. Means as claimed in claim 5, wherein said 'rack is mounted on said second carriagetonpermit variations.- of inclination with respect to the movement of said second carriage.

7. 'Means as claimed in claim 5, wherein said second carriage is'provided with a groove parallel to said rack and a roller is mounted on-said body to run in said. groove:

8. Means asclaimed in claim 5,v whereinlsaid rack :is

mounted on said second carriage to permit :va-riationsofr inclination with respect to the movement of said second. I

References Cited-in the file of this patent UNITED STATES PATENTS 1 1,470,932 Perras= Oct; 169192 3" 1,802,678 Smith Apr. 28, 19%1 2,551,261. Gensheimer 1 May 1, 1951 

